Comprehensive Web App Testing

I'm looking for a thorough testing of my web app, www.roundleap.com. The primary focus should be on validating the main features and user journeys.

Key areas to test include:
- Creating an account, logging in, and managing a profile
- Using the main service or tool offered by the app
- Making payments, bookings, or other transactions

Testing should be conducted on both desktop/laptop and mobile devices.

Ideal Skills and Experience:
- Experience in web app testing
- Familiarity with user journey mapping
- Strong attention to detail
- Ability to document findings clearly and concisely